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Altera_Forum
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16 years ago

ALTLVDS pins io standard

hi, I am using ALTLVDS megacore for serialization and deserialization. the serializer has tx_out : OUT STD_LOGIC_VECTOR (0 DOWNTO 0) and the deserializer has rx_in : IN STD_LOGIC_VECTOR ...
Altera_Forum's avatar
Altera_Forum
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16 years ago

It's sufficient to assign LVDS IO standard to the logical pin. The location must be the positive pin of a differential pair. The negative pin is also displayed in the Pin Planner tool, but you don't need to assign it anyway. You can even delete the negative pin entry from the Pin Planner list. The handling of negative differential pins isn't actually consistent throughout the different Quartus tools, it seems confusing in part.